what are the disadvantages of RPC with respect to message passing?

Question

what are the disadvantages of RPC with respect to message passing?

Answer 1

As a general rule, RPC provides a higher level of abstraction than some other means of interprocess communication. This makes it, perhaps, easier to use than lower level primitives. For this abstraction you may pay some penalty in performance due to marshaling/unmarshaling and may have to deal with added complexity in configuration for simple scenarios.

You might be interested in this thesis (pdf) by Jackie Silcock which discusses differences between message passing, RPC, and distributed shared memory with respect to several different measures of performance and implementation. You can also read one of the papers based on the thesis: Message Passing, Remote Procedure Calls and Distributed Shared Memory as Communication Paradigms for Distributed Systems (pdf)